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    <title>Document</title>
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    <script>
      let arr = [1, 23, 43, 12, 44, 52, 77, 36]
      function sem(a) {
        let sum = 0
        for (let i = 0; i < a.length; i++) {
          if (a[i] % 2 === 1) {
            sum += a[i]
          }
        }
        return sum / a.length
      }
      let res = sem(arr)
      console.log(res)
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